Structure-based design of phthalimide derivatives as potential cyclooxygenase-2 (COX-2) inhibitors: anti-inflammatory and analgesic activities

Eur J Med Chem. 2015 Mar 6:92:115-23. doi: 10.1016/j.ejmech.2014.12.039. Epub 2014 Dec 24.

Abstract

A group of 30 cyclic imides (1-10a-c) was designed for evaluation as a selective COX-2 inhibitor and investigated in vivo for anti-inflammatory and analgesic activities. Compounds 6a, 6b, 7a and 7b exhibit optimal COX-2 inhibitory potency (IC50 = 0.18, 0.24, 0.28 and 0.36 μM; respectively) and selectivity index (SI) range of 363-668. In vitro COX-1/COX-2 inhibition structure-activity studies identified compound 6a as a highly potent (IC50 = 0.18 μM), and an extremely selective [COX-2 (SI) = 668] comparable to celecoxib [COX-2 (SI) > 384], COX-2 inhibitor that showed superior anti-inflammatory activity (ED50 = 54.0 mg/kg) relative to diclofenac (ED50 = 114 mg/kg). Molecular Docking study of the synthesized compound 6a into the active site of COX-2 revealed a similar binding mode to SC-558, a selective COX-2 inhibitor. Docking study showed that the methoxy moeities of 6a inserted deep inside the 2°-pocket of the COX-2 active site, where the O-atoms of such groups underwent an H-bonding interaction with His(90) (3.02 Å), Arg(513) (1.94, 2.83 Å), and Gln(192) (3.25 Å).

Keywords: Analgesic activity; Anti-inflammatory activity; COX-2 inhibitors; Molecular docking; Phthalimides.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analgesics / chemical synthesis
  • Analgesics / chemistry
  • Analgesics / pharmacology*
  • Animals
  • Anti-Inflammatory Agents, Non-Steroidal / chemical synthesis
  • Anti-Inflammatory Agents, Non-Steroidal / chemistry
  • Anti-Inflammatory Agents, Non-Steroidal / pharmacology*
  • Carrageenan
  • Cyclooxygenase 2 Inhibitors / chemical synthesis
  • Cyclooxygenase 2 Inhibitors / chemistry
  • Cyclooxygenase 2 Inhibitors / pharmacology*
  • Drug Design*
  • Edema / chemically induced
  • Edema / drug therapy
  • Male
  • Models, Molecular
  • Molecular Structure
  • Phthalimides / chemical synthesis
  • Phthalimides / chemistry
  • Phthalimides / pharmacology*
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Analgesics
  • Anti-Inflammatory Agents, Non-Steroidal
  • Cyclooxygenase 2 Inhibitors
  • Phthalimides
  • phthalimide
  • Carrageenan